Considering the high incidence of autism spectrum disorder (ASD) (latest CDC estimate: 1 in 50), its impact on family stress and medical costs, and the devastating effects of its associated communication deficits on long-term outcomes, research aimed at improving language and cognitive skills in this population in early childhood is critical. We seek to understand conditions underlying successful language development in young children with ASD in order to develop interventions that are most likely to promote their language and cognitive skills, and to improve their educational, vocational, and personal outcomes. Specifically, we focus on improving receptive vocabulary, or understanding of word meanings, in children with ASD. Receptive vocabulary knowledge is a prerequisite to further language development. It is therefore critical for interventions in the infant, toddler, and preschool years to increase receptive vocabulary in children with disabilities. The goal of this proposal is to discover conditions under which children with ASD acquire receptive vocabulary meanings, retain them over time, and generalize them to new exemplars differing slightly from those with which the word was initially presented. As yet little is known about the cognitive processes underlying word learning in ASD. It is therefore likely that we have not discovered the optimal conditions for promoting learning in interventions. We concentrate on two processes that impact learning in typical development, but have not been well studied in ASD: 1) use of linguistic context to acquire word meanings, and 2) consolidation of memories during sleep. First, we ask if-given the social impairments associated with ASD-children with ASD acquire word meanings more successfully in non-social and non-interactive contexts, but rich linguistic contexts. We compare performance in a non-social context to a social context modeled on standard therapies. Second, we ask if understanding memory consolidation in ASD can improve our ability to promote retention and generalization of word meanings. This work will provide a basis for new interventions to increase receptive vocabulary. In future work, we will use the findings to develop and test such an intervention. This proposal is intended to provide the PI with a structured career development plan that will allow her to carry out this research, building on her extensive background in language development in typically developing populations, and adding expertise in two new areas: 1) language development in young children with ASD, and 2) sleep-dependent memory consolidation as it relates to language learning. The training provided by this award will transition the PI from basic research in language development to an independent career in translational research, studying language learning in populations with communication disorders.